The invention relates to the transmission of a router advertisement message from a router from a mobile anchor point in a network to a possibly mobile node.
In a first publication www.ietf.org/internet-drafts/draft-soliman-mobileip-hmipv6-00.txt of 7.5.2000, a hierarchical mobile Internet protocol is presented which transmits a special message from a mobile anchor point (MAP) through a router network to a receiving mobile node. In this method, the routers of the mobile anchor points periodically send out router advertisement messages or respond to router inquiries. Future versions of this protocol will possibly include that receivers quietly ignore any options which do not recognize and forward these messages. The mobile anchor point is configured in such a manner that it receives or forwards its options or options forwarded from other mobile anchor points at special interfaces. The option of the mobile anchor point is forwarded within the hierarchy. Each router along this path up to the access router to the network will change the hop limits in the router advertisement message if a router, which is also a mobile anchor point, receives a router advertisement from another mobile anchor point, should the latter add its own MAP option to this and forward the two options to the further hierarchy level. The draft provides that all routers acquire the message, evaluate the payload, change it and send it out again. However, this requires special routers in the entire network.